* fix(build): Prevent duplicated client/server generated code
The tonic-build process collects up RPC services as they are provided by
prost, before writing them out as part of the finalization step for a
given protocol buffer package.
In the case of imported protocol buffer packages, there may be RPC
services included by import in addition to those in the top-level
package. Therefore it is necessary to make sure each set of
client/server services gathered by tonic-build is cleared after the
finalization process for a given protocol buffer package, otherwise they
will be incorrectly aggregated as the generation process proceeds
through the subsequent packages.
* Test case for duplicated client/server generated code
A simple test case that will fail to build without a fix to prevent
RPC services being duplicated into inappropriate modules (that related
to particular protocol buffer packages).
* Additional test case for included_service
Introduces an additional case that captures making sure services defined
before including a package with additional services doesn't
incidentially clear such precursor services from the including package.
* Fix unnecessary newline to keep `cargo fmt` happy
* chore: Add tags to .gitignore
When generating ctags/universal-ctags, a 'tags' file is generated. This
commit adds any generted 'tags' file to .gitignore.
* feat(build): Expose type_attribute and field_attribute
This commit exposes the `type_attribute` and `field_attribute`
configuration settings from Prost. These are useful to tweak/extend the
generated types.
For example:
```
tonic_build::configure()
.out_dir(tmp)
.format(false)
.type_attribute(".", "#[derive(Serialize, Deserialize)]")
.type_attribute(".", "#[serde(rename_all = \"camelCase\")]")
.field_attribute("in", "#[serde(rename = \"in\")]")
.compile(&["tests/protos/wellknown.proto"], &["tests/protos"])
.unwrap();
```
Would add the serde `Serialize` and `Deserialize` traits, while renaming
all the fields to camelCase, and having serde keep fields named `in`
named `in`, rather than Prost's `in_`, to every type generated by Prost.
* generate rustdoc comments from .proto file comments
* move imports to top of file
* more docs gen
* trait docs
* more docs
* use singular doc gen fn here
* remove pesky space
