Add a BPMN 2.0 cheat sheet and one-page PDF (#109)

Author: transitrix

MANIFEST.md

@@ -57,6 +57,8 @@ admits future files.
 - `library/acme-architecture-on-a-page/index.html`
 - `library/archimate-cheat-sheet/archimate-cheat-sheet.pdf`
 - `library/archimate-cheat-sheet/index.html`
+- `library/bpmn-cheat-sheet/bpmn-cheat-sheet.pdf`
+- `library/bpmn-cheat-sheet/index.html`
 - `library/csvlod-cheat-sheet/csvlod-cheat-sheet.pdf`
 - `library/csvlod-cheat-sheet/index.html`
 - `library/index.html`

library/SHA256SUMS

@@ -1,3 +1,4 @@
 93a3843aa900dfe0c4d3cefe6aae027b22e1f3ee405530d6306fb1675f408760  archimate-cheat-sheet/archimate-cheat-sheet.pdf
 c6081219bb46ba4f528693ab14a01624e4d821bf833cc4474e95f70f1b6483c3  acme-architecture-on-a-page/acme-architecture-on-a-page.pdf
 f395038d991974a097f458b5f8f4eee2bf8a260d093aa8e7c97914a09aaff940  csvlod-cheat-sheet/csvlod-cheat-sheet.pdf
+4ce16701c1ab198dc3e0f1730e3b664f00c551d8e75823b50aae1839d35dec41  bpmn-cheat-sheet/bpmn-cheat-sheet.pdf