Merge pull request #569 from CliMA/he/2m-api-docs

update 2M API docs format

Author: haakon-e

docs/bibliography.bib

@@ -747,3 +747,15 @@ @article{Gunn1949
   year={1949},
   publisher={American Meteorological Society}
 }
+
+@article{WackerSeifert2001,
+  title = {Evolution of rain water profiles resulting from pure sedimentation: Spectral vs. parameterized description},
+  journal = {Atmospheric Research},
+  volume = {58},
+  number = {1},
+  pages = {19-39},
+  year = {2001},
+  issn = {0169-8095},
+  doi = {10.1016/S0169-8095(01)00081-3},
+  author = {Ulrike Wacker and Axel Seifert},
+}

docs/src/API.md

@@ -41,11 +41,24 @@ Microphysics1M.snow_melt
 # 2-moment precipitation microphysics
 ```@docs
 Microphysics2M
-Microphysics2M.LiqRaiRates
+```
+## Size distributions
+
+### Parameters
+```@docs
 Microphysics2M.pdf_cloud_parameters
 Microphysics2M.pdf_rain_parameters
+```
+
+### Size distributions
+```@docs
 Microphysics2M.size_distribution
 Microphysics2M.get_size_distribution_bound
+```
+
+## Rates
+```@docs
+Microphysics2M.LiqRaiRates
 Microphysics2M.autoconversion
 Microphysics2M.accretion
 Microphysics2M.liquid_self_collection