automatically install deps as part of build

.travis.yml

@@ -4,10 +4,7 @@ os: linux
 install:
   - sudo apt-get update
   - sudo apt-get install portaudio19-dev npm
-  - pip install -r requirements.txt
-  - pip install -r requirements.dev
   - pip install pyqt5 pyqtwebengine
-  - (cd ts && npm i)
 
 jobs:
   include:

Makefile

@@ -51,7 +51,7 @@ clean:
 	rm -rf .build
 	rm -rf $(JSDEPS)
 
-build: .build/ui .build/js
+build: reqs .build/ui .build/js
 
 .build/ui: $(shell find designer -name '*.ui')
 	./tools/build_ui.sh
@@ -92,3 +92,18 @@ JSDEPS := $(patsubst ts/src/%.ts, web/%.js, $(TSDEPS))
 .build/js: $(TSDEPS)
 	(cd ts && ./node_modules/.bin/tsc --build)
 	touch $@
+
+.PHONY: reqs
+reqs: .build/pyrunreqs .build/pydevreqs .build/jsreqs
+
+.build/pyrunreqs: requirements.txt
+	pip install -r $<
+	touch $@
+
+.build/pydevreqs: requirements.dev
+	pip install -r $<
+	touch $@
+
+.build/jsreqs: ts/package.json
+	(cd ts && npm i)
+	touch $@

README.development

@@ -13,30 +13,20 @@ provide support for problems you encounter when running from source.
 To start, make sure you have the following installed:
 
  - Python 3.6+
- - Qt 5.9.x or 5.11.x+, and a PyQT that supports it
+ - Qt 5.9.x or 5.11.x+
  - portaudio
  - mpv
  - lame
  - npm
 
-Now install the python dependencies:
+If your distro provides PyQt5 and PyQt5-WebEngine packages, you can
+install them as well. If you go that path, make sure you install pyqt5-dev-tools
+as well.
 
-$ pip3 install -r requirements.txt
-$ pip3 install -r requirements.dev
-
-If you're on a Linux distribution that packages a compatible Qt then you can
-use the distro's packages. Make sure you install the development tools (eg
-pyqt5-dev-tools) as well.
-
-If you're on another platform or your distro has the wrong Qt version, you
-can install PyQt with pip:
+Otherwise, install them with pip:
 
 $ pip3 install PyQt5 PyQtWebEngine
 
-And after that, install the js dependencies:
-
-$ (cd ts && npm i)
-
 Then to run the development version:
 
 $ make run